View Full Version : Bypass Valve Actuator/IC info..

01-22-2007, 01:46 PM
I have to say I am less the happy with the results of a very expensive rebuild. The power "advertised" is simply just not there. I'm not saying it's junk, perhaps something is missing or not working properly. I had more power stock.

My boost gauge claims that I'm at 15 +/-1. SC makes on hell of a great sound..yet my head remains to be slammed into the headrest like I want. Only option I have yet to do is add a bigger IC....Almost ordered the big FMIC from SCP today...she's on sale. (do I need to rip out the AC for that?)

Am I loosing power via the bypass and if so how can I tell?

01-22-2007, 02:03 PM
Hate to say spetz but I told ya so. :) ;) Sorry you had to learn that yourself. You should have come down for the dyno day when XR7 Dave was here. You could have been grumpy/angry with me.

Your not losing power via the bypass.

I thought you already did a bigger IC? Yes, yes it is a good option. I've got one on my car. Looks great and lots of cooling capability. No, the nice part is you get to KEEP your A/C! :)

Some things I'd like you to note:
- You seriously need a tune
- After the IC you'll need a set of heads to take full advantage of all your modifications. This is the next logical step in the build of your car. After heads/IC/Tune you should be over 300 HP without a hitch. :)

Your almost there, don't give up yet!

*Edit: Could you please provide a full modification list?

01-22-2007, 02:07 PM
You haven't given any of us enough information to even speculate about what needs to be done to help.

I even took a look at your cardomain page...There's not a lot of info there either. Just because you have a rebuilt engine, that doesn't equate to more power. What did you do to the engine? Raise the compression, cam, ported heads? How well do the heads flow? Does it have a dyno tune? etc.

There's a whole lot that you could tell us that might be able to help, but until you provide the info, we'd just be shooting in the dark.

01-22-2007, 10:51 PM

Let's start by me saying I'm realistic. I was not exspecting to be twisting off drive shaft's and makeing 11 second passes. I'm just a little dissapointed is all. Lot's of time and $$$.

The motor was rebuilt, but there was a small problem. I had no knowledge of it actually happening. Lets just say some one got on a break away without the puck. I did catch the heads in time to have them re-done a little better than stock. ie: after market (not saying thats better) and some porting. I do not have the flow rates.

So lets assume the motor is a stock rebuild, .30 over...It's fresh. And "advertised" add on's from "said" site's have stock engine. The cam is a Competition Cam SPECS:

RPM Operating Range: 1500-6000 RPM
Duration: Advertised Intake 265, Advertised Exhaust 281.
@ .050" Intake 210, @ .050" Exhaust 226
Valve Lift: Intake .500, Exhaust .500
Lobe Separation Angle: 114

Not much of a difference from stock I understand.

The SC mod you all know. Ported SC and the larger plenum for the rear...even opted for the raised top. MP III supposed to add quite a bit of power. I'm sure this mod has been bolted on old motors with good results. 85 mm throttle body and the air intake with a 76mm MAF. The exaughst I finally finished with contains mid lenth headers (up to +20hp) with 2 1/2" true dual stainless with the same size Magnaflows and resonators. Guys did a great job of the pipes..gotta post some pics.

I made sure she not starving for fuel. I even added that little gauge that turned all brown from heat right on the fuel rail. 255 lph pump and 42# injectors. In hind sight I might have gone bigger but told this was all I needed.

BHJ balancer and billet pulley's. There's 10% overdrive on the SC and 5% on the jackshaft. Even had Dave tune a chip...via email...Your right...should have gone to Calgary. Yet to have it Dynoed/tuned, gotta find the right place. That and a foot of snow in my driveway.

All this and I almost got my ~~~ handed to me by a 05 Duramax....that's a diesel FYI.

I'm not sure I want to blow more money on a FMIC.

01-22-2007, 11:03 PM
There's no substitute for an actual tune, not a mail order. You're probably so rich, it's killing you power. It's hard for anyone to say though.

01-22-2007, 11:26 PM

Your basically in the same boat as I am.
Only difference is that I am using a Magnum Powers FMIC and no cam. I've got Dave doing me up a set of heads and a cam so I can call this project 'done'. As per getting your tune XR7 Dave is coming to Calgary again this spring. Keep in touch with me and I'll get you set up.

Now to your situation: The way I see it you have two corks left.

Cork 1 - With your 'ported' heads I have some pretty big concerns. There is a 'right' way of porting them and a 'wrong' way of porting them. Specifically when it comes to the exhaust side. I really hope whoever ported them did not just assume 'bigger=better'. If they did really mess with the exhaust side I'd seriously consider replacing them back with a stock set. If you would really like to step it up contact XR7 Dave for a set of heads.
Cork 2 - Inter cooler, do you at least have a fan on yours? If not consider that your budget modification for under $100 until you can afford a front mount. Once you have a FMIC you can turn the boost up some more. The recommended amount of OD with a MPIII is 25%.

Either way you look at it you have about $3000 more to go. :p
Which order you do this in is up to you. Heads would give you the best punch, couple that with at least a $100 IC fan until you can afford a FMIC.

(FYI: Whoever sold you those headers is full of ~~~~. I'm sure they sound and look great but for actually performance I'd say no more then maybe 5? HP)

XR7 Dave
01-22-2007, 11:48 PM
The chip holds a basically stock tune but with the correct calibrations for the 42lb injectors so that the EEC can work as programmed from Ford. This is not typically a bad tune but it's obviously done blind so there are no guarantees to it's accuracy. If you find an SCT dealer local to tune it I can send you the base file for them so that all they have to do is tune the air/fuel ratio. I doubt the car is excessively rich so as to where it wouldn't make power. Commanded AFR is 11.0 and C&L meters tend to lean you out a little from there.

That cam is decent. It's very similar to the one that I used at over 400rwhp although the 114LSA isnt' helping N/A performance any. If the heads are even half way decent they will at least help.

By driving your MPIII only 15% you are leaving a lot of low rpm efficiency on the table. Chances are it doesn't make massive boost at low rpm, and then you have an oversized exhaust which isn't helping, and a cam that is eating up a little bit of bottom end. That all adds up to something that on one hand wants to rev, but on the other hand, is it safe to really rev the crap out of it with no tune? It could be very lean on top and you wouldn't know it until something bad happened. And then we haven't even talked about that stock IC yet. Heat is a big killer.

It think it's most likely the combination that's hurting you. Stock manifolds with 2.25" downpipes would have been a lot cheaper and performed better at your mod level.

But with the MPIII that wants to move a lot of air and a cam to back it up, you need more IC and more OD to get the most of it so in that case your current exhaust isn't all bad.

Your boost gauge means next to nothing. It could be right or it could be way off. But if you aren't getting a true 15psi by 3000rpm then you don't have enough OD.


And then tuning of course but the tune isn't going to make a bunch of power, it's mainly going to make it safe.

I can do some long distance tuning if you can get access to a WB02 and get me some datalogs. Still a royal ~~~~ but if you can't find someone local...

01-23-2007, 12:42 PM
All the info regarding horse came from either the SCP or Magnum sites..as well as the advise of the guy on the phone selling me the package. "headers are a must!!" I'm inclined to agree that 5hp sounds about right, not the 20hp BS!! I know headers work wonders on V8 like a charm. I was hoping for a throaty sound though...which I like.

No problem with the heads being over done..just a mild hone to clean the up.

As for the tune I knew we were grasping at straws..just wanted to clean up the idle, which it did...But she does run rich. I had a problem with the Livewires I bought also. One broke off at the plug and when i replaced it she ran like crap.

I'm really thinking about the FMIC...Probably the best thing I can do to finish her off. Probably wasted like 2000.00 on useless stuff but as long as oil prices are high I'm laughing.

02-20-2007, 01:21 PM
OK guy's....FMIC is on the way, should see it this week. :)

02-20-2007, 02:55 PM
Have you had the car dyno'd? The seat of your pants dyno can be easily fooled. You can be making much more HP, but same torque at a higher RPM, but you wont get that neck snapping power feeling.

A proper tune WILL make a significant increase in power. With the wrong AFR and ignition map you will be slow and possibly in danger of blowing your engine.

Porting for a forced induction engine is different in some aspects than for a NA engine. Straight is best, period. Different sizes of ports will make power at different rpm bands. The key is to keep air speed a certain (don't recall how much) percent under the speed of sound. Resistance goes up exponentially as you near the speed of sound. High air velocity will help not only combustion, but it will help keep the cylinder filling past BDC.

What intercooler are you using? Roots blowers make huge amounts of heat when you start spinning them faster. At a point, you will be making more boost only because the air is much hotter.

Good luck getting the power you are after,

02-20-2007, 06:04 PM

From your description, it sounds as if SOMETHING is not right about how your motor runs -- I was toying with a 2003 Dodge Cummins PU the other day, and had no problem with accelerating away from him, at will -- true, he came out of the light and pulled two car lengths -- I was not willing to fry the tires to get going -- once I got moving, I pulled up on him in second gear, out in front by a car once I hit third -- and toyed with him off/on the gas while he was throttling it hard -- and I am running a 100% stock 1990 SC 5-speed.

COULD be that the Duramax had some serious power mods done to it -- modified versions of some of the diesel trucks will flat out FLY when accelerating.

I am not convinced that adding the FMIC is going to help you much -- apparently, something ELSE is WAAY out of kilter -- methinks your computer profile is working against you, and needs remapping to properly account for/utilize the new/updated parts and mods -- from the list of parts/mods and what not that you have listed, you SHOULD be making GOOD power.


02-21-2007, 10:46 AM
I'm going with the Magnum IC. Looks great in pic's and the install seems easy. I'm pretty sure your right about the motor not running properly. The chip I installed made no serious difference after I installed it. the car run's well and it idles with no studders either. I'm sure it's something stupid.

I work in an area where every bloody truck is a 8 inck lifted diesel...all makes, and all have chips, air ans exaughst. Most sound like airplanes taking off and they make sick horsepower and amazing torque. My friends 04 duramax will break loose on the highway doing 80 km/h and spin!! Such easy mods...Plug and play. Not like ours.....tweaking and adjusting never stops.